Valve seat grinding tool



Feb. 12, 1946. P. WEYNAND I VALVE SEAT-GRINDING TOOL 'Filed Sept. 15. 1945 2 Sheets-Sheet 1 Inventor ibazjfynazzdk a d Attorneys Feb.,12, 1946. P. WEYNAND VALVE SEAT GRINDING TOOL 2 Shets-Sheet 2 Filed Sept. 15, 1943 Patented Feb. 12, 1946 UNITED STATES PATENT OFFICE VALVE SEATGRINDINGLTOOL .Paul Weynand, San Antonio,Tex. Application September 15, 1943,-SerialNo. 502,513

3 Claims.

This invention appertains to new and useful improvements in valve seat grinding tools and more particularly to a tool especially adapted for grinding aeroplane engine valve seats.

The method nOW commonly used in grinding aeroplane engine valve seats is first attaching the cylinder to a base on the grinding machine which necessitates securing the grinding stone pilot securely into the valve guide by means of a locking type pilot. The stone is then fitted to a projecting shaft and the seat is ground by electric motor coupled to a flexible shaft connected to the stone drive. This method cuts the valve seats true only in relation to the valve guide, the pilot being locked securely into the guide, the seating surface of the valve is then cut on another machineand is sometimes cut many times to find the angle to fit the ground valve seat.

The principal object of the present invention is to preserve the merits of the above method, but to shorten the overall operation by the provision of a specially constructed tool.

Other objects and advantages of the invention will become apparent to the reader of the following description.

In the drawings:

Figure 1 represents a fragmentary detailed sectional view showing a valve seat with the improved tool in working relation with respect thereto.

Figure 2 is a perspective view of the power coupling.

Figure 3 is a perspective View of the grindingstone.

Figure 4 is a fragmentary side elevational view showing a special type of coupling for driving the stone shaft from the guide end thereof.

Figure 5 is a fragmentary detailed sectional View through the power coupling shown in Figure 4.

Referring to the drawings wherein like numerals designate like parts, it can be seen that Figure 1 shows a portion of an engine including one valve seat and the tool being driven from the outer end. In this connection, numeral 5 denotes a portion of the engine, while numeral 6 denotes a beveled valve seat. A tubular guide I is provided for accommodating the usual valve stem (not shown) and through this is disposed a shaft 8, forming part of the present invention.

This shaft may be driven from either end, depending upon requirements, and one end is threaded as at 9 to accommodate a coupling generally referred to by numeral II) when the shaft is driven from the left hand in Figure 1.

Numeral -l I denotes a grinding stone having a beveled face, at the bevel of the seat 6. This stone II has an internally threaded centrally located bushing I2 and the stone is adapted to be screwed onto the threaded portion 9 and against a shoulder l3 of said shaft 8. F p

A pair of washers l4, l5 are provided on the shaft 8, one to abut the shoulder I3 and the other to abut the adjacent end of the guide sleeve 1, and a compression spring [6 is interposed between these washers, for the purpose of maintaining the stone ll urged a slight distance away from the valve seat 6.

The coupling [0 consists of a pair of annular members l1, I8, the member l'lbeing internally threaded to coact with the threads 9 of the shaft 8, while the ring I8 is provided with a polygonallyshaped openings to receive a motor driven tool (not shown). Interposed between the annular members l1, la is an annular cap member 20 of some resilient material such as rubber forming a cushion for the threaded end of the shaft, and this annulus 20 is provided with laterally disposed portionsZl which are received by grooves in the annular members l'l, I8. Thus a flexible connection is provided between the members [1, [8,

A power driven tool is engaged with the annular member N3 of the coupling Ill, and by exerting pressure against the resistance of the spring IS, the stone l I can be brought into working engagement with the seat 6.

For driving the shaft 8 from the right end as shown in Figure 4, a special coupling generally referred to by numeral 22 is provided.

The coupling 22 consists of a block 23 having a bore 24 therethrough for receiving a slotted barrel 25 of spring metal from which a power,

tool engageable shank 26 projects. The barrel 25 is adapted to receive one end of the shaft 8 and is adapted to be compressed to snugly engage the shaft 8 by a wedge member 2'! operating against the tapered formation 28 in a pocket 29. Swivelly connected to this wedge member 23 is one end of a screw shaft 30 which is feedable through the block 23 and has a polygonalthe same valve machine, automatically securing the same angle on both the valve and seat.

While the foregoing specification sets forth the invention in specific terms, it is to be understood that numerous changes in the shape, size and materials may be resorted to without departing from the spirit and scope of the invention as claimed hereinafter.

Having described the claimed as new is:

1. A valve grinder comprising a shaft, a grindinvention, what is ing stone on the shaft, a member for rotating the stone and shaft, a resilient coupling between .the stone and the rotating member, said shaft serving as a pilot, said coupling consisting of a cup secured to the shaft, a resilient insert in the cup, a socket anchored in the insert and to which the rotating member is attachable.

2. A valve grinder comprising a shaft, a grinding stone on the shaft, a member for rotating the 20 stone and shaft, a resilient coupling between the stone and the rotating member, said shaft serving as a pilot, said coupling consisting of a cup secured to the shaft, a resilient insert in the cup, a socket anchored in the insert and to which the rotating member is attachable, said insert being removable from the cup.

3. A valve grinder comprising a shaft, a grinding stone on the shaft, a member for rotating the stone and shaft, a resilient coupling between the stone and the rotating member, said shaft serving as a pilot, said coupling consisting of a cup secured to the shaft, a resilient insert in the cup, a socket anchored in the insert and to which the rotating member is attachable, said insert being removable from the cup, and a retaining spring ring for holding the insert against displacement from the cup.

PAUL WEYNAND. 

